This invention is directed to diaminothiazole compounds that modulate and/or inhibit the activity of certain protein kinases, and to pharmaceutical compositions containing such compounds. The invention is also directed to the therapeutic or prophylactic use of such compounds and compositions, and to methods of treating cancer as well as other disease states associated with unwanted angiogenesis and/or cellular proliferation, by administering effective amounts of such compounds.
Protein kinases are a family of enzymes that catalyze phosphorylation of the hydroxy group of specific tyrosine, serine, or threonine residues in proteins. Typically, such phosphorylation dramatically perturbs the function of the protein, and thus protein kinases are pivotal in the regulation of a wide variety of cellular processes, including metabolisim, cell proliferation, cell differentiation, and cell survival. Of the many different cellular functions in which the activity of protein kinases is known to be required, some processes represent attractive targets for therapeutic intervention for certain disease states. Two examples are angiogenesis and cell-cycle control, in which protein kinases play a pivotal role; these processes are essential for the growth of solid tumors as well as for other diseases.
Angiogenesis is the mechanism by which new capillaries are formed from existing vessels. When required, the vascular system has the potential to generate new capillary networks in order to maintain the proper functioning of tissues and organs. In the adult, however, angiogenesis is fairly limited, occurring only in the process of wound healing and neovascularization of the endometrium during menstruation. See Merenmies et al., Cell Growth and Differentiation, 8, 3-10 (1997). On the other hand, unwanted angiogenesis is a hallmark of several diseases, such as retinopathies, psoriasis, rheumatoid arthritis, age-related macular degeneration (AMD), and cancer (solid tumors). Folkman, Nature Med., 1, 27-31 (1995). Protein kinases which have been shown to be involved in the angiogenic process include three members of the growth factor receptor tyrosine kinase family: VEGF-R2 (vascular endothelial growth factor receptor 2, also known as KDR (kinase insert domain receptor) and as FLK-1); FGF-R (fibroblast growth factor receptor); and TEK (also known as Tie-2).
VEGF-R2, which is expressed only on endothelial cells, binds the potent angiogenic growth factor VEGF and mediates the subsequent signal transduction through activation of its intracellular kinase activity. Thus, it is expected that direct inhibition of the kinase activity of VEGF-R2 will result in the reduction of angiogenesis even in the presence of exogenous VEGF (see Strawn et al., Cancer Research, 56, 3540-3545 (1996)), as has been shown with mutants of VEGF-R2 which fail to mediate signal transduction. Millauer et al., Cancer Research, 56, 1615-1620 (1996). Furthermore, VEGF-R2 appears to have no function in the adult beyond that of mediating the angiogenic activity of VEGF. Therefore, a selective inhibitor of the kinase activity of VEGF-R2 would be expected to exhibit little toxicity.
Similarly, FGF-R binds the angiogenic growth factors aFGF and bFGF and mediates subsequent intracellular signal transduction. Recently, it has been suggested that growth factors such as bFGF may play a critical role in inducing angiogenesis in solid tumors that have reached a certain size. Yoshiji et al., Cancer Research, 57, 3924-3928 (1997). Unlike VEGF-R2, however, FGF-R is expressed in a number of different cell types throughout the body and may or may not play important roles in other normal physiological processes in the adult. Nonetheless, systemic administration of a small-molecule inhibitor of the kinase activity of FGF-R has been reported to block bFGF-induced angiogenesis in mice without apparent toxicity. Mohammadi et al., EMBO Journal, 17, 5896-5904 (1998).
TEK (also known as Tie-2) is another receptor tyrosine kinase expressed only on endothelial cells which has been shown to play a role in angiogenesis. The binding of the factor angiopoietin-1 results in autophosphorylation of the kinase domain of TEK and results in a signal transduction process which appears to mediate the interaction of endothelial cells with peri-endothelial support cells, thereby facilitating the maturation of newly formed blood vessels. The factor angiopoietin-2, on the other hand, appears to antagonize the action of angiopoietin-1 on TEK and disrupts angiogenesis. Maisonpierre et al., Science, 277, 55-60 (1997).
As a result of the above-described developments, it has been proposed to treat angiogenesis by the use of compounds inhibiting the kinase activity of VEGF-R2, FGF-R, and/or TEK For example, WIPO International Publication No. WO 97/34876 discloses certain cinnoline derivatives that are inhibitors of VEGF-R2, which may be used for the treatment of disease states associated with abnormal angiogenesis and/or increased vascular permeability such as cancer, diabetes, psoriasis, rheumatoid arthritis, Kaposi""s sarcoma, haemangioma, acute and chronic nephropathies, atheroma, arterial restinosis, autoimmune diseases, acute inflammation and ocular diseases with retinal vessel proliferation.
In addition to its role in angiogenesis, protein kinases also play a crucial role in cell-cycle control. Uncontrolled cell proliferation is the insignia of cancer. Cell proliferation in response to various stimuli is manifested by a de-regulation of the cell division cycle, the process by which cells multiply and divide. Tumor cells typically have damage to the genes that directly or indirectly regulate progression through the cell division cycle.
Cyclin-dependent kinases (CDKs) are serine-threonine protein kinases that play critical roles in regulating the transitions between different phases of the cell cycle. See, e.g., the articles compiled in Science, 274, 1643-1677 (1996). CDK complexes are formed through association of a regulatory cyclin subunit (e.g., cyclin A, B1, B2, D1, D2, D3, and E) and a catalytic kinase subunit (e.g., cdc2 (CDK1), CDK2, CDK4, CDK5, and CDK6). As the name implies, the CDKs display an absolute dependence on the cyclin subunit in order to phosphorylate their target substrates, and different kinase/cyclin pairs function to regulate progression through specific phases of the cell cycle.
It is CDK4 complexed to the D cyclins that plays a critical part in initiating the cell-division cycle from a resting or quiescent stage to one in which cells become committed to cell division. This progression is subject to a variety of growth regulatory mechanisms, both negative and positive. Aberrations in this control system, particularly those that affect the function of CDK4, have been implicated in the advancement of cells to the highly proliferative state characteristic of malignancies, particularly familial melanomas, esophageal carcinomas, and pancreatic cancers. See, e.g., Kamb, Trends in Genetics, 11, 136-140 (1995); Kamb et al., Science, 264, 436-440 (1994).
The use of compounds as anti-proliferative therapeutic agents that inhibit CDKs is the subject of several patent publications. For example, U.S. Pat. No. 5,621,082 to Xiong et al. discloses nucleic acid encoding an inhibitor of CDK6, and European Patent Publication No. 0 666 270 A2 describes peptides and peptide mimetics that act as inhibitors of CDK1 and CDK2. WIPO International Publication No. WO 97/16447 discloses certain analogs of chromones that are inhibitors of cyclin-dependent kinases, in particular of CDK/cyclin complexes such as CDK4/cyclin D1, which may be used for inhibiting excessive or abnormal cell proliferation, and therefore for treating cancer. WIPO International Publication No. WO 99/21845 describes 4-aminothiazole derivatives that are useful as CDK inhibitors.
There is still a need, however, for small-molecule compounds that may be readily synthesized and are effective in inhibiting one or more CDKs or CDK/cyclin complexes. Because CDK4 may serve as a general activator of cell division in most cells, and complexes of CDK4 and D-type cyclins govern the early G1 phase of the cell cycle, there is a need for effective inhibitors of CDK4, and D-type cyclin complexes thereof, for treating one or more types of tumors. Also, the pivotal roles of cyclin E/CDK2 and cyclin B/CDK1 kinases in the G1/S phase and G2/M transitions, respectively, offer additional targets for therapeutic intervention in suppressing deregulated cell-cycle progression in cancer.
Another protein kinase, CHK1, plays an important role as a checkpoint in cell-cycle progression. Checkpoints are control systems that coordinate cell-cycle progression by influencing the formation, activation and subsequent inactivation of the cyclin-dependent kinases. Checkpoints prevent cell-cycle progression at inappropriate times, maintain the metabolic balance of cells while the cell is arrested, and in some instances can induce apoptosis (programmed cell death) when the requirements of the checkpoint have not been met. See, e.g., O""Connor, Cancer Surveys, 29, 151-182 (1997); Nurse, Cell, 91, 865-867 (1997); Hartwell et al., Science, 266, 1821-1828 (1994); Hartwell et al., Science, 246, 629-634 (1989).
One series of checkpoints monitors the integrity of the genome and, upon sensing DNA damage, these xe2x80x9cDNA damage checkpointsxe2x80x9d block cell-cycle progression in G1 and G2 phases, and slow progression through S phase. O""Connor, Cancer Surveys, 29, 151-182 (1997); Hartwell et al., Science, 266, 1821-1828 (1994). This action enables DNA repair processes to complete their tasks before replication of the genome and subsequent separation of this genetic material into new daughter cells takes place. Importantly, the most commonly mutated gene in human cancer, the p53 tumor-suppressor gene, produces a DNA damage checkpoint protein that blocks cell-cycle progression in G1 phase and/or induces apoptosis (programmed cell death) following DNA damage. Hartwell et al., Science, 266, 1821-1828 (1994). The p53 tumor suppressor has also been shown to strengthen the action of a DNA damage checkpoint in G2 phase of the cell cycle. See, e.g., Bunz et al., Science, 282, 1497-1501 (1998); Winters et al., Oncogene, 17, 673-684 (1998); Thompson, Oncogene, 15, 3025-3035 (1997).
Given the pivotal nature of the p53 tumor suppressor pathway in human cancer, therapeutic interventions that exploit vulnerabilities in p53-defective cancer have been actively sought. One emerging vulnerability lies in the operation of the G2 checkpoint in p53 defective cancer cells. Cancer cells, because they lack G1 checkpoint control, are particularly vulnerable to abrogation of the last remaining barrier protecting them from the cancer-killing effects of DNA-damaging agents: the G2 checkpoint. The G2 checkpoint is regulated by a control system that has been conserved from yeast to humans. Important in this conserved system is a kinase, CHK1, which transduces signals from the DNA-damage sensory complex to inhibit activation of the cyclin B/Cdc2 kinase, which promotes mitotic entry. See, e.g., Peng et al., Science, 277, 1501-1505 (1997); Sanchez et al., Science, 277, 1497-1501 (1997). Inactivation of CHK1 has been shown to both abrogate G2 arrest induced by DNA damage inflicted by either anticancer agents or endogenous DNA damage, as well as result in preferential killing of the resulting checkpoint defective cells. See, e.g., Nurse, Cell, 91, 865-867 (1997); Weinert, Science, 277, 1450-1451 (1997); Walworth et al., Nature, 363, 368-371 (1993); and Al-Khodairy et al., Molec. Biol. Cell, 5, 147-160 (1994).
Selective manipulation of checkpoint control in cancer cells could afford broad utilization in cancer chemotherapeutic and radiotherapy regimens and may, in addition, offer a common hallmark of human cancer xe2x80x9cgenomic instabilityxe2x80x9d to be exploited as the selective basis for the destruction of cancer cells. A number of factors place CHK1 as a pivotal target in DNA-damage checkpoint control. The elucidation of inhibitors of this and functionally related kinases such as Cds1/CHK2, a kinase recently discovered to cooperate with CHK1 in regulating S phase progression (see Zeng et al., Nature, 395, 507-510 (1998); Matsuoka, Science, 282, 1893-1897 (1998)), could provide valuable new therapeutic entities for the treatment of cancer.
Integrin receptor binding to ECM initiates intracellular signals mediated by FAK (Focal Adhesion Kinase) that are involved in cell motility, cellular proliferation, and survival. In human cancers, FAK overexpression is implicated in tumorigenesis and metastatic potential through its role in integrin mediated signaling pathways.
Tyrosine kinases can be of the receptor type (having extracellular, transmembrane and intracellular domains) or the non-receptor type (being wholly intracellular). At least one of the non-receptor protein tyrosine kinases, namely, LCK, is believed to mediate the transduction in T-cells of a signal from the interaction of a cell-surface protein (Cd4) with a cross-linked anti-Cd4 antibody. A more detailed discussion of non-receptor tyrosine kinases is provided in Bolen, Oncogene, 8, 2025-2031 (1993), which is incorporated herein by reference
In addition to the protein kinases identified above, many other protein kinases have been considered to be therapeutic targets, and numerous publications disclose inhibitors of kinase activity, as reviewed in the following: McMahon et al, Oncologist, 5, 3-10 (2000); Holash et al., Oncogene, 18, 5356-62 (1999); Thomas et al., J. Biol. Chem., 274, 36684-92 (1999); Cohen, Curr. Op. Chem. Biol., 3, 459-65 (1999); Klohs et al., Curr. Op. Chem. Biol., 10, 544-49 (1999); McMahon et al., Current Opinion in Drug Discovery and Development, 1, 131-146 (1998); Strawn et al., Exp. Opin. Invest. Drugs, 7, 553-573 (1998). WIPO International Publication WO 00/18761 discloses certain substituted 3-cyanoquinolines as protein kinase inhibitors. As is understood by those skilled in the art, it is desirable for kinase inhibitors to possess both high affinity for the target kinase as well as high selectivity versus other protein kinases.
The present invention relates to compounds falling within formula I below which modulate and/or inhibit the activity of protein kinases, as well as to pharmaceutically acceptable prodrugs, pharmaceutically active metabolites, and pharmaceutically acceptable salts thereof (such compounds, prodrugs, metabolites and salts are collectively referred to as xe2x80x9cagentsxe2x80x9d). The invention is also directed to pharmaceutical compositions containing such agents and their therapeutic use in treating diseases mediated by kinase activity, such as cancer, as well as other disease states associated with unwanted angiogenesis and/or cellular proliferation, such as diabetic retinopathy, neovascular glaucoma, rheumatoid arthritis and psoriasis. Further, the invention is related to methods of modulating and/or inhibiting the kinase activity associated with VEGF-R, FGF-R, CDK complexes, TEK, CHK1, LCK, and FAK.
In one general aspect, the invention relates to protein kinase inhibitors of the Formula I: 
wherein:
R1 is hydrogen, a substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or a group of the formula R6xe2x80x94CO or R6xe2x80x94CS where R6 is substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, alkenyl, aryl, heteroaryl, alkoxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen or substituted or unsubstituted alkyl, aryl, or heteroaryl;
R2 is hydroxy, halo, cyano, or nitro, or substituted or unsubstituted alkyl, alkenyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (A) 
where Ra is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (B) 
where Ra is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (C) 
where Rb and Rc are independently hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (D) 
where Rd is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, hydroxy, alkoxy, amino, alkylamino, dialkylamino, or acylamino, and Re is hydrogen, alkyl, cycloalkyl heterocycloalkyl, aryl, heteroaryl, amino, alkylamino, or dialkylamino, or
a group of the formula (E) 
where Rf is alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (F) 
where Rg and Rh are each independently hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl, or
a group of the formula (G) 
where Ri is alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or a group of formula (A), formula (B), formula (C), formula (H), or formula (I) as defined herein, or
a group of the formula (H) 
where Rj is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, hydroxy, alkoxy, amino, or a group of formula (A), formula (B), formula (C) or formula (D) as defined herein, and Rk is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or a group of formula (A), formula (B), formula (C), formula (D), formula (E), or formula (F) as defined herein, or
a group of the formula (I) 
where R1 is hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or a group of formula (C) as defined herein,
or R2 is a substituted or unsubstituted cycloalkyl, heterocycloalkyl, or aryl that is fused to Q;
X is C or N; and
Q is a divalent radical having 2 or 3 ring atoms (in the ring formed by Q together with X, C* and N* in Formula I) each independently selected from C, N, O, S, Cxe2x80x94R5 and Nxe2x80x94R5, where R5 is alkyl, aryl, heteroaryl, alkoxy, hydroxy, halo, cyano, or amino, which together with C* and N* (in Formula I) form a five- or six-membered aromatic or nonaromatic ring.
The invention is also directed to pharmaceutically acceptable prodrugs, pharmaceutically active metabolites, and pharmaceutically acceptable salts of the compounds of Formula I.
In a preferred general embodiment, the invention relates to compounds having the Formula II: 
wherein:
R1 is substituted or unsubstituted aryl or heteroaryl, or a group of the formula R6xe2x80x94CO or R6xe2x80x94CS where R6 is substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl alkenyl, aryl, heteroaryl, alkoxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen or a substituted or unsubstituted alkyl, aryl, or heteroaryl;
R2 is as defined above;
X is C or N; and
Y and Z are each independently C, N, S, O, Cxe2x80x94R5 or Nxe2x80x94R5 where R5 is as defined above;
and pharmaceutically acceptable prodrugs, pharmaceutically active metabolites, and pharmaceutically acceptable salts thereof. Advantageous methods of making the compounds of the Formula II are also described.
More preferably, the invention is directed to compounds of Formula II wherein: R1 is substituted or unsubstituted aryl or heteroaryl, or R6xe2x80x94CO or R6xe2x80x94CS where R6 is substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, alkenyl, aryl, heteroaryl, alkoxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen or substituted or unsubstituted alkyl, aryl, or heteroaryl; R2 is substituted or unsubstituted aryl or heteroaryl; X and Y are each independently C or N; and Z is S or O. In another preferred embodiment of compounds of the Formula II, R1 and R2 are each independently substituted aryl, X is C, Y is C or N, and Z is S or O. More preferably, R1 is a substituted or unsubstituted alkyl, R2 is a substituted aryl, X is C, Y is C or N, and Z is S or O.
In another preferred general embodiment, the invention relates to compounds of Formula III: 
wherein:
R1 is substituted or unsubstituted aryl or heteroaryl, or R6xe2x80x94CO or R6xe2x80x94CS where R6 is a substituted or unsubstituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl;
R3 is substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl;
R4 is hydrogen, hydroxy, lower alkyl, halo, lower alkoxy, amino, nitro, or trifluoromethyl; and
Y and Z are each independently C, N, S, O, Cxe2x80x94R5 or Nxe2x80x94R5 where R5 is unsubstituted or substituted alkyl or aryl;
as well as pharmaceutically acceptable prodrugs, pharmaceutically acceptable metabolites, and pharmaceutically acceptable salts thereof.
Especially preferred are compounds of Formula IV: 
wherein:
R1 is substituted or unsubstituted aryl or heteroaryl, or R6xe2x80x94CO where R6 is a substituted or unsubstituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, cycloalkyl, heterocycloalkyl, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl;
R3 is substituted or unsubstituted alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy, aryloxy, or Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl;
R4 is independently selected from hydrogen, hydroxy, lower alkyl, halo, lower alkoxy, amino, nitro, and trifluoromethyl;
Y is C or N; and
Z is S or O;
as well as pharmaceutically acceptable prodrugs, pharmaceutically acceptable metabolites, and pharmaceutically acceptable salts thereof.
More preferably, the invention is directed to compounds of Formula IV, wherein:
R1 is substituted or unsubstituted aryl or heteroaryl, or R6xe2x80x94CO where R6 is Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl; R3 is substituted or unsubstituted alkyl, aryl, heteroaryl, or alkoxy; R4(a) and R4(b) are independently hydrogen, lower alkyl, or halo; Y is C or N; and Z is S or O. Even more preferred are compounds of Formula IV, wherein: R1 is substituted or unsubstituted aryl or heteroaryl, or R6xe2x80x94CO where R6 is Nxe2x80x94R7R8 where R7R8 are each independently hydrogen, alkyl, aryl, or heteroaryl; R3 is substituted or unsubstituted aryl, heteroaryl, or alkoxy; R4(a) is chloro, fluoro, or methyl; R4(b) is fluoro; Y is N; and Z is O.
The invention also relates to a method of modulating and/or inhibiting the kinase activity of VEGF-R, FGF-R, TEK, a CDK complex, CHK1, TEK, LCK, and/or FAK by administering a compound of the formula I or a pharmaceutically acceptable prodrug, pharmaceutically active metabolites, or pharmaceutically acceptable salt thereof. There is also provided compounds of the present invention that have selective kinase activityxe2x80x94i.e., they possess significant activity against one specific kinase while possessing less or minimal activity against a different kinase. In one preferred embodiment of the invention, compounds of the present invention are those of Formula I possessing substantially higher potency against VEGF receptor tyrosine kinase than against FGF-R1 receptor tyrosine kinase. The invention is also directed to methods of modulating VEGF receptor tyrosine kinase activity without significantly modulating FGF receptor tyrosine kinase activity.
The invention also relates to pharmaceutical compositions each comprising: an effective amount of an agent selected from compounds of Formula I and pharmaceutically acceptable salts, pharmaceutically active metabolites, and pharmaceutically acceptable prodrugs thereof; and a pharmaceutically acceptable carrier or vehicle for such agent. The invention further provides methods of treating cancer as well as other disease states associated with unwanted angiogenesis and/or cellular proliferation, comprising administering effective amounts of such agents to a patient in need of such treatment.
The inventive compounds of the Formula I, II, III, and IV are useful for mediating the activity of protein kinases. More particularly, the compounds are useful as anti-angiogenesis agents and as agents for modulating and/or inhibiting the activity of protein kinases, thus providing treatments for cancer or other diseases associated with cellular proliferation mediated by protein kinases.
The term xe2x80x9calkylxe2x80x9d as used herein refers to straight- and branched-chain alkyl groups having one to twelve carbon atoms. Exemplary alkyl groups include methyl (Me), ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl (t-Bu), pentyl, isopentyl, tert-pentyl, hexyl, isohexyl, and the like. The term xe2x80x9clower alkylxe2x80x9d designates an alkyl having from 1 to 8 carbon atoms (a C1-8-alkyl). Suitable substituted alkyls include fluoromethyl, difluoromethyl, trifluoromethyl, 2-fluoroethyl, 3-fluoropropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, and the like.
The term xe2x80x9calkenylxe2x80x9d refers to straight- and branched-chain alkenyl groups having from two to twelve carbon atoms. Illustrative alkenyl groups include prop-2-enyl, but-2-enyl, but-3-enyl, 2-methylprop-2-enyl, hex-2-enyl, and the like.
The term xe2x80x9ccycloalkylxe2x80x9d refers to partially saturated or unsaturated carbocycles having from three to twelve carbon atoms, including bicyclic and tricyclic cycloalkyl structures. Suitable cycloalkyls include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like.
A xe2x80x9cheterocycloalkylxe2x80x9d is intended to mean a partially saturated or unsaturated monocyclic radical containing carbon atoms, preferably 4 or 5 ring carbon atoms, and at least one heteroatom selected from nitrogen, oxygen and sulfur.
The terms xe2x80x9carylxe2x80x9d (Ar) and xe2x80x9cheteroarylxe2x80x9d refer to monocyclic and polycyclic unsaturated or aromatic ring structures, with xe2x80x9carylxe2x80x9d referring to those that are carbocycles and xe2x80x9cheteroarylxe2x80x9d referring to those that are heterocycles. Examples of aromatic ring structures include phenyl, naphthyl, 1,2,3,4-tetrahydronaphthyl, furyl, thienyl, pyrrolyl, pyridyl, pyridinyl, pyrazolyl, imidazolyl, pyrazinyl, pyridazinyl, 1,2,3-triazinyl, 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1-H-tetrazol-5-yl, indolyl, quinolinyl, benzofuranyl, benzothiophenyl (thianaphthenyl), and the like. Such moieties may be optionally substituted by one or more suitable substituents, for example, a substituent selected from a halogen (F, Cl, Br or I); lower alkyl; OH; NO2; CN; CO2H; O-lower alkyl; aryl; aryl-lower alkyl; CO2CH3; CONH2; OCH2CONH2; NH2; SO2NH2; OCHF2; CF3; OCF3; and the like. Such moieties may also be optionally substituted by a fused-ring structure or bridge, for example OCH2xe2x80x94O.
The term xe2x80x9calkoxyxe2x80x9d is intended to mean the radical xe2x80x94O-alkyl. Illustrative examples include methoxy, ethoxy, propoxy, and the like. The term xe2x80x9clower alkoxyxe2x80x9d designates an alkoxy having from 1 to 8 carbon atoms
The term xe2x80x9caryloxyxe2x80x9d represents xe2x80x94O-aryl, where aryl is defined above.
The term xe2x80x9chalogenxe2x80x9d represents chlorine, fluorine, bromine or iodine. The term xe2x80x9chaloxe2x80x9d represents chloro, fluoro, bromo or iodo.
In general, the various moieties or functional groups for variables in the formulae may be optionally substituted by one or more suitable substituents. Exemplary substituents include a halogen (F, Cl, Br, or I), lower alkyl, xe2x80x94OH, xe2x80x94NO2, xe2x80x94CN, xe2x80x94CO2H, xe2x80x94O-lower alkyl, -aryl, -aryl-lower alkyl, xe2x80x94CO2CH3, xe2x80x94CONH2, xe2x80x94OCH2CONH2, xe2x80x94NH2, xe2x80x94SO2NH2, haloalkyl (e.g., xe2x80x94CF3, xe2x80x94CH2CF3), xe2x80x94O-haloalkyl (e.g., xe2x80x94OCF3, xe2x80x94OCHF2), and the like.
The terms xe2x80x9ccomprisingxe2x80x9d and xe2x80x9cincludingxe2x80x9d are used in an open, non-limiting sense.
Compounds of the invention are encompassed by Formula I. Although Formula I depicts a double bond between C* and N*, the artisan will understand that when Q together with C* and N* form a five- or six-membered aromatic ring, the presence of the double bond is not necessarily between C* and N*, as other canonical forms of the aromatic ring exist. It is therefore understood that all possible canonical forms of the aromatic ring formed by Q together with C* and N* are also intended to be covered by Formula I. The compounds of the invention are preferably those of the Formula II, more preferably those of the Formula III, and even more preferably those of the Formula IV.
Some of the inventive compounds may exist as single stereoisomers (i.e., essentially free of other stereoisomers), racemates, and/or mixtures of enantiomers and/or diastereomers. All such single stereoisomers, racemates and mixtures thereof are intended to be within the scope of the present invention. Preferably, the inventive compounds that are optically active are used in optically pure form.
As generally understood by those skilled in the art, an optically pure compound having one chiral center (i.e., one asymmetric carbon atom) is one that consists essentially of one of the two possible enantiomers (i.e., is enantiomerically pure), and an optically pure compound having more than one chiral center is one that is both diastereomerically pure and enantiomerically pure. Preferably, the compounds of the present invention are used in a form that is at least 90% optically pure, that is, a form that contains at least 90% of a single isomer (80% enantiomeric excess (xe2x80x9ce.e.xe2x80x9d) or diastereomeric excess (xe2x80x9cd.e.xe2x80x9d)), more preferably at least 95% (90% e.e. or d.e.), even more preferably at least 97.5% (95% e.e. or d.e.), and most preferably at least 99% (98% e.e. or d.e.).
Additionally, the formulas are intended to cover solvated as well as unsolvated forms of the identified structures. For example, Formula I includes compounds of the indicated structure in both hydrated and non-hydrated forms. Other examples of solvates include the structures in combination with isopropanol, ethanol, methanol, DMSO, ethyl acetate, acetic acid, or ethanolamine.
In addition to compounds of the Formula I, II, III, and IV, the invention includes pharmaceutically acceptable prodrugs, pharmaceutically active metabolites, and pharmaceutically acceptable salts of such compounds.
A xe2x80x9cpharmaceutically acceptable prodrugxe2x80x9d is a compound that may be converted under physiological conditions or by solvolysis to the specified compound or to a pharmaceutically acceptable salt of such compound.
A xe2x80x9cpharmaceutically active metabolitexe2x80x9d is intended to mean a pharmacologically active product produced through metabolism in the body of a specified compound or salt thereof. Metabolites of compound may be identified using routine techniques known in the art and their activities determined using tests such as those described herein.
A xe2x80x9cpharmaceutically acceptable saltxe2x80x9d is intended to mean a salt that retains the biological effectiveness of the free acids and bases of the specified compound and that is not biologically or otherwise undesirable. A compound of the invention may possess a sufficiently acidic, a sufficiently basic, or both functional groups, and accordingly react with any of a number of inorganic or organic bases, and inorganic and organic acids, to form a pharmaceutically acceptable salt. Exemplary pharmaceutically acceptable salts include those salts prepared by reaction of the compounds of the present invention with a mineral or organic acid or an inorganic base, such as salts including sulfates, pyrosulfates, bisulfates, sulfites, bisulfites, phosphates, monohydrogenphosphates, dihydrogenphosphates, metaphosphates, pyrophosphates, chlorides, bromides, iodides, acetates, propionates, decanoates, caprylates, acrylates, formates, isobutyrates, caproates, heptanoates, propiolates, oxalates, malonates, succinates, suberates, sebacates, fumarates, maleates, butyne-1,4-dioates, hexyne-1,6-dioates, benzoates, chlorobenzoates, methylbenzoates, dinitrobenzoates, hydroxybenzoates, methoxybenzoates, phthalates, sulfonates, xylenesulfonates, phenylacetates, phenylpropionates, phenylbutyrates, citrates, lactates, xcex3-hydroxybutyrates, glycollates, tartrates, methane-sulfonates, propanesulfonates, naphthalene-1-sulfonates, naphthalene-2-sulfonates, and mandelates.
If the inventive compound is a base, the desired pharmaceutically acceptable salt may be prepared by any suitable method available in the art, for example, treatment of the free base with an inorganic acid, such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like, or with an organic acid, such as acetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, malonic acid, pyrovic acid, oxalic acid, glycolic acid, salicylic acid, a pyranosidyl acid, such as glucuronic acid or galacturonic acid, an alpha-hydrozy acid, such as citric acid or tartaric acid, an amino acid, such as aspartic acid or glutamic acid, an aromatic acid, such as benzoic acid or cinnamic acid, a sulfonic acid, such as p-toluenesulfonic acid or ethanesulfonic acid, or the like.
If the inventive compound is an acid, the desired pharmaceutically acceptable salt may be prepared by any suitable method, for example, treatment of the free acid with an inorganic or organic base, such as an amine (primary, secondary or tertiary), an alkali metal hydroxide or alkaline earth metal hydroxide, or the like. Illustrative examples of suitable salts include organic salts derived from amino acids, such as glycine and arginine, ammonia, primary, secondary, and tertiary amines, and cyclic amines, such as piperidine, morpholine and piperazine, and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum and lithium.
In the case of agents that are solids, it is understood by those skilled in the art that the inventive compounds and salts may exist in different crystal or polymorphic forms, all of which are intended to be within the scope of the present invention and specified formulas.
Therapeutically effective amounts of the agents of the invention may be used to treat diseases mediated by modulation or regulation of protein kinases. An xe2x80x9ceffective amountxe2x80x9d is intended to mean that amount of an agent that, when administered to a mammal in need of such treatment, is sufficient to effect treatment for a disease mediated by the activity of one or more protein kinases, such as tryosine kinases. Thus, e.g., a therapeutically effective amount of a compound of the Formula I, salt, active metabolite or prodrug thereof is a quantity sufficient to modulate, regulate, or inhibit the activity of one or more protein kinases such that a disease condition which is mediated by that activity is reduced or alleviated. The amount of a given agent that will correspond to such an amount will vary depending upon factors such as the particular compound, disease condition and its severity, the identity (e.g., weight) of the mammal in need of treatment, but can nevertheless be routinely determined by one skilled in the art. xe2x80x9cTreatingxe2x80x9d is intended to mean at least the mitigation of a disease condition in a mammal, such as a human, that is affected, at least in part, by the activity of one or more protein kinases, such as tyrosine kinases, and includes: preventing the disease condition from occurring in a mammal, particularly when the mammal is found to be predisposed to having the disease condition but has not yet been diagnosed as having it; modulating and/or inhibiting the disease condition; and/or alleviating the disease condition.
The inventive agents may be prepared using the reaction routes and synthesis schemes as described below, employing the techniques available in the art using starting materials that are readily available.
In one general synthetic process, compounds of Formula I are prepared according to the following reaction scheme: 
A solution of an isothiocyanate, e.g., R1xe2x80x94Nxe2x95x90Cxe2x95x90S and cyanamide is reacted with 1.1 to 1.5 molar equivalents of 1,8-diazabicylclo[5.4.0]undec-7-ene (xe2x80x9cDBUxe2x80x9d) in a suitable solvent, such as acetonitrile, at an appropriate temperature (preferably room temperature) for approximately 40-80 minutes, generating intermediate V. Without isolation, intermediate V is further allowed to react with a compound of Formula VI, where LG is a suitable leaving group such as chloro, bromo, or mesyloxy, under the same conditions for an additional 0.5 to 24 hours (h) to yield a compound of Formula VII.
In some instances, the compound of Formula VII is not isolated, but is directly converted to the compound of Formula I by continued reaction at a temperature between room temperature and 80xc2x0 C., preferably 50xc2x0 C., for 1 to 24 h. Conventional work-up and purification yields final compound I. Alternatively, a compound of Formula VII is isolated and purified, and then is converted to a compound of Formula I by treatment with a suitable base, such as potassium t-butoxide, lithium hexamethyldisilazide, or lithium diisopropylamide, in an appropriate solvent, such as THF, for 0.5 to 24 h at a temperature between xe2x88x9278xc2x0 C. and room temperature. Various compounds of Formula VI are commercially available or known, for example, 2-(chloromethyl)benzimidazole, 2-(chloromethyl)quinoline, 2-picolyl chloride, 2-acetamido-4-(chloromethyl)thiazole, 6-(chloromethyl)-2-isopropylpyrimidin-4-ol, 4-chloromethyl-2-(4-chlorophenyl)thiazole, 3-(chloromethyl)-1,2,4-oxadiazole, 3-(chloromethyl)-5-(3,5-dimethylisoxazol-4-yl)-1,2,4-oxadiazole, 3-bromomethyl-6,7-dimethoxy-1-methyl-2(1h)-quinoxalinone, 2-chloromethyl-5-methoxybenzimidazole, 5-(tert-butyl)-3-(chloromethyl)-1,2,4-oxadiazole, 5-chloro-3-(chloromethyl)-1,2,4-thiadiazole, 3-(chloromethyl)-5-(3-thienyl)-1,2,4-oxadiazole, 5-[4-(chloromethyl)-1,3-thiazol-2-yl]isoxazole, 5-(chloromethyl)-3-[3,5-di(trifluoromethyl)styryl]-1,2,4-oxadiazole, 5-chloro-4-(chloromethyl)-1,2,3-thiadiazole, 5-(chloromethyl)-3-(4-chlorophenyl)-1,2,4-oxadiazole, 3-chloro-2-(chloromethyl)-5-(trifluoromethyl)pyridine, 5-(chloromethyl)-3-[(2-pyridylsulfonyl)methyl]-1,2,4-oxadiazole, 3-(chloromethyl)-5-methylisoxazole, 2-chloromethyl-4,6-dimethoxypyrimidine, 3-(chloromethyl)-5-(4-chlorophenyl)-4H-1,2,4-triazole, 2-(chloromethyl)-5-(4-chlorophenyl)-1,3,4-oxadiazole, 4-chloromethyl-5-methyl-2-phenyl-oxazole, 3-(chloromethyl)-1-(3,5-dichlorophenyl)-5-methyl-1h-pyrazole, and 3-(chloromethyl)-5-(1,2,3-thiadiazol-4-yl)-1,2,4-oxadiazole. Compounds of Formula VI may also be prepared by methods known to those skilled in the art. See, e.g., Mylari et al., J. Med. Chem., 35, 457-465 (1992); Baiocchi et al., Heterocyclic Chem., 16, 1469-1474 (1979), which are incorporated by reference herein.
A compound of Formula VIII may be prepared by conventional acylation of 3-aminobenzonitrile, followed by heating at 60-100xc2x0 C. with hydroxylamine in a suitable solvent, such as ethanol or isopropanol, for 1 to 24 hours. A compound of Formula VI(a) may be prepared by treatment of a compound of Formula VIII with chloroacetyl chloride and a suitable base, such as diispropylethylamine (xe2x80x9cDIEAxe2x80x9d), in an appropriate solvent, such as dichloromethane. Conventional aqueous work-up provides a crude intermediate, which is further heated at 100xc2x0 C. in a suitable solvent, such as dioxane, for 0.5 to 4 hours, to yield, after conventional isolation and purification, a compound of Formula VI(a). 
Compounds of Formula II, where X is C and Y and Z are independently C, N, or O, may also be prepared by the above described general procedure. To an R1-isothiocyanate solution in acetonitrile is added cyanamide, followed by the addition of DBU, while maintaining the internal temperature of the reaction at approximately 15-30xc2x0 C. After stirring 1-2 hours, a suitable reactant that allows for the cyclization and formation as described above of a compound of Formula II is added in the presence of a catalytic amount of tetra-butylammonium iodide. For example, the reaction of 3-chloromethyl-5-R2-[1,2,4]oxadiazole (VI(a)) with compound VII for about two hours at approximately 50xc2x0 C. provides after purification the cyclized compound II(a). 
Inventive compounds of Formulas II, III, and IV may also be prepared by other processes, including the general procedure shown in the following reaction scheme. 
A compound of Formula II, where X and Y are C and Z is S, may be prepared by adding DBU to a solution of R1-isothiocyanato and cyanamide in a suitable solvent at an appropriate temperature, preferably acetonitrile at room temperature for approximately 40-80 minutes. To this reaction mixture is added bromo-acetonitrile and additional DBU, to yield, after conventional work-up and purification, an intermediate 2-R1-amino-4-amino-thiazole-5-carbonitrile intermediate IX. The reaction of intermediate IX with dihydrogen sulfide in triethylamine/pyridine at about 0xc2x0 C. provides intermediate X. Intermediate X is converted to a compound II(b) by stirring a solution of compound X and 2-bromo-1-R2-ethanone in methanol overnight at room temperature. After removal of the methanol, the crude compound II(b) is worked up using conventional isolation techniques and purified using silica column chromatography.
Compounds of Formula II(c) may also be prepared directly from compound X by reacting it with a xcex1-bromo-acetic acid ester or a xcex1-bromolactone under the same conditions as described in the preparation of compounds II(b). 
By treating compound IX with a suitable 2-amino-alcohol and a catalytic amount of ZnCl2, a compound of Formula II(d) is produced after standard acid work-up and purification by silica chromatography. Compounds of Formula II(e) may also be prepared from compounds IX by refluxing in a suitable aprotic solvent, such as toluene, a solution of IX, TMSN3, and a catalytic amount of Bu2SnO. After refluxing, the solvent is removed and the residue is redissolved in ethyl acetate, washed with a appropriate aqueous acid solution, and dried over a suitable drying agent. After the removal of the solvent, the residue is triturated in ethyl ether and compound II(e) is collected by filtration. 
Compounds of Formula III may also be prepared directly from compound II(b) where R2 is 3-nitrophenyl by reducing the nitro group with a suitable reducing agent to form the amino substituted phenyl (II(f)). Preferably, a solution of compound II(b) where R2 is 3-nitrophenyl and stannous chloride is dissolved in dimethylformamide (xe2x80x9cDMFxe2x80x9d) under inert atmosphere conditions and stirred at between 40-60xc2x0 C. until II(f) is formed.
The intermediate II(f) may be reacted with a suitable acylating agent under standard acylating conditions to form a compound of the Formula III(a). A preferable acylating procedure involves dissolving compound II(f) in DMF and tetrahydrofuran (xe2x80x9cTHFxe2x80x9d) and adding pyridine and a suitable acid chloride or acyl chloroformate at xe2x88x9230 to 0xc2x0 C. The reaction is quenched with a proton source (e.g., methanol) and purified by preparative C-18 reverse phase HPLC to provide compound III(a). 
Other compounds of Formula I may be prepared in manners analogous to the general procedures described above or the detailed procedures described in the examples herein. The affinity of the compounds of the invention for a receptor may be enhanced by providing multiple copies of the ligand in close proximity, preferably using a scaffolding provided by a carrier moiety. It has been shown that provision of such multiple valence compounds with optimal spacing between the moieties dramatically improves binding to a receptor. See for example, Lee et al., Biochem, 23, 4255 (1984). The multivalency and spacing can be controlled by selection of a suitable carrier moiety or linker units. Such moieties include molecular supports which contain a multiplicity of functional groups that can be reacted with functional groups associated with the compounds of the invention. Of course, a variety of carriers can be used, including proteins such as BSA or HAS, a multiplicity of peptides including, for example, pentapeptides, decapeptides, pentadecapeptides, and the like. The peptides or proteins can contain the desired number of amino acid residues having free amino groups in their side chains; however, other functional groups, such as sulfhydryl groups or hydroxyl groups, can also be used to obtain stable linkages.
Compounds that potently regulate, modulate, or inhibit the protein kinase activity associated with receptors, FGF, CDK complexes, TEK, CHK1, LCK, and FAK, among others, and which inhibit angiogenesis and/or cellular profileration is desirable and is one preferred embodiment of the present invention. The present invention is further directed to methods of modulating or inhibiting protein kinase activity, for example in mammalian tissue, by administering an inventive agent. The activity of the inventive compounds as modulators of protein kinase activity, such as the activity of kinases, may be measured by any of the methods available to those skilled in the art, including in vivo and/or in vitro assays. Examples of suitable assays for activity measurements include those described in Parast C. et al., BioChemistry, 37, 16788-16801 (1998); Jeffrey et al., Nature, 376, 313-320 (Jul. 27, 1995); WIPO International Publication No. WO 97/34876; and WIPO International Publication No. WO 96/14843. These properties may be assessed, for example, by using one or more of the biological testing procedures set out in the examples below.
The active agents of the invention may be formulated into pharmaceutical compositions as described below. Pharmaceutical compositions of this invention comprise an effective modulating, regulating, or inhibiting amount of a compound of Formula I, II, III or IV and an inert, pharmaceutically acceptable carrier or diluent. In one embodiment of the pharmaceutical compositions, efficacious levels of the inventive agents are provided so as to provide therapeutic benefits involving modulation of protein kinases. By xe2x80x9cefficacious levelsxe2x80x9d is meant levels in which the effects of protein kinases are, at a minimum, regulated. These compositions are prepared in unit-dosage form appropriate for the mode of administration, e.g., parenteral or oral administration.
An inventive agent is administered in conventional dosage form prepared by combining a therapeutically effective amount of an agent (e.g., a compound of Formula I) as an active ingredient with appropriate pharmaceutical carriers or diluents according to conventional procedures. These procedures may involve mixing, granulating and compressing or dissolving the ingredients as appropriate to the desired preparation.
The pharmaceutical carrier employed may be either a solid or liquid. Exemplary of solid carriers are lactose, sucrose, talc, gelatin, agar, pectin, acacia, magnesium stearate, stearic acid and the like. Exemplary of liquid carriers are syrup, peanut oil, olive oil, water and the like. Similarly, the carrier or diluent may include time-delay or time-release material known in the art, such as glyceryl monostearate or glyceryl distearate alone or with a wax, ethylcellulose, hydroxypropylmethylcellulose, methylmethacrylate and the like.
A variety of pharmaceutical forms can be employed. Thus, if a solid carrier is used, the preparation can be tableted, placed in a hard gelatin capsule in powder or pellet form or in the form of a troche or lozenge. The amount of solid carrier may vary, but generally will be from about 25 mg to about 1 g. If a liquid carrier is used, the preparation will be in the form of syrup, emulsion, soft gelatin capsule, sterile injectable solution or suspension in an ampoule or vial or non-aqueous liquid suspension.
To obtain a stable water-soluble dose form, a pharmaceutically acceptable salt of an inventive agent is dissolved in an aqueous solution of an organic or inorganic acid, such as 0.3M solution of succinic acid or citric acid. If a soluble salt form is not available, the agent may be dissolved in a suitable cosolvent or combinations of cosolvents. Examples of suitable cosolvents include, but are not limited to, alcohol, propylene glycol, polyethylene glycol 300, polysorbate 80, gylcerin and the like in concentrations ranging from 0-60% of the total volume. In an exemplary embodiment, a compound of Formula I is dissolved in DMSO and diluted with water. The composition may also be in the form of a solution of a salt form of the active ingredient in an appropriate aqueous vehicle such as water or isotonic saline or dextrose solution.
It will be appreciated that the actual dosages of the agents used in the compositions of this invention will vary according to the particular complex being used, the particular composition formulated, the mode of administration and the particular site, host and disease being treated. Optimal dosages for a given set of conditions can be ascertained by those skilled in the art using conventional dosage-determination tests in view of the experimental data for an agent. For oral administration, an exemplary daily dose generally employed is from about 0.001 to about 1000 mg/kg of body weight, with courses of treatment repeated at appropriate intervals. Administration of prodrugs are typically dosed at weight levels which are chemically equivalent to the weight levels of the fully active form.
The compositions of the invention may be manufactured in manners generally known for preparing pharmaceutical compositions, e.g., using conventional techniques such as mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or lyophilizing. Pharmaceutical compositions may be formulated in a conventional manner using one or more physiologically acceptable carriers, which may be selected from excipients and auxiliaries that facilitate processing of the active compounds into preparations which can be used pharmaceutically.
Proper formulation is dependent upon the route of administration chosen. For injection, the agents of the invention may be formulated into aqueous solutions, preferably in physiologically compatible buffers such as Hanks""s solution, Ringer""s solution, or physiological saline buffer. For transmucosal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art.
For oral administration, the compounds can be formulated readily by combining the active compounds with pharmaceutically acceptable carriers known in the art. Such carriers enable the compounds of the invention to be formulated as tablets, pills, dragees, capsules, liquids, gels, syrups, slurries, suspensions and the like, for oral ingestion by a patient to be treated. Pharmaceutical preparations for oral use can be obtained using a solid excipient in admixture with the active ingredient (agent), optionally grinding the resulting mixture, and processing the mixture of granules after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients include: fillers such as sugars, including lactose, sucrose, mannitol, or sorbitol; and cellulose preparations, for example, maize starch, wheat starch, rice starch, potato starch, gelatin, gum, methyl cellulose, hydroxypropylmethyl-cellulose, sodium carboxymethylcellulose, or polyvinylpyrrolidone (PVP). If desired, disintegrating agents may be added, such as crosslinked polyvinyl pyrrolidone, agar, or alginic acid or a salt thereof such as sodium alginate.
Dragee cores are provided with suitable coatings. For this purpose, concentrated sugar solutions may be used, which may optionally contain gum arabic, polyvinyl pyrrolidone, Carbopol gel, polyethylene glycol, and/or titanium dioxide, lacquer solutions, and suitable organic solvents or solvent mixtures. Dyestuffs or pigments may be added to the tablets or dragee coatings for identification or to characterize different combinations of active agents.
Pharmaceutical preparations which can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer, such as glycerol or sorbitol. The push-fit capsules can contain the active ingredients in admixture with fillers such as lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate, and, optionally, stabilizers. In soft capsules, the active agents may be dissolved or suspended in suitable liquids, such as fatty oils, liquid paraffin, or liquid polyethylene glycols. In addition, stabilizers may be added. All formulations for oral administration should be in dosages suitable for such administration. For buccal administration, the compositions may take the form of tablets or lozenges formulated in conventional manner.
For administration intranasally or by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebuliser, with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit may be determined by providing a valve to deliver a metered amount. Capsules and cartridges of gelatin for use in an inhaler or insufflator and the like may be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.
The compounds may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit-dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents.
Pharmaceutical formulations for parenteral administration include aqueous solutions of the active compounds in water-soluble form. Additionally, suspensions of the active agents may be prepared as appropriate oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Aqueous injection suspensions may contain substances which increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Optionally, the suspension may also contain suitable stabilizers or agents which increase the solubility of the compounds to allow for the preparation of highly concentrated solutions.
For administration to the eye, a compound of the Formula I, II, III, or IV is delivered in a pharmaceutically acceptable ophthalmic vehicle such that the compound is maintained in contact with the ocular surface for a sufficient time period to allow the compound to penetrate the corneal and internal regions of the eye, including, for example, the anterior chamber, posterior chamber, vitreous body, aqueous humor, vitreous humor, cornea, iris/cilary, lens, choroid/retina and selera. The pharmaceutically acceptable ophthalmic vehicle may be an ointment, vegetable oil, or an encapsulating material. A compound of the invention may also be injected directly into the vitreous and aqueous humor.
Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use. The compounds may also be formulated in rectal compositions such as suppositories or retention enemas, e.g, containing conventional suppository bases such as cocoa butter or other glycerides.
In addition to the formulations described above, the compounds may also be formulated as a depot preparation. Such long-acting formulations may be administered by implantation (for example, subcutaneously, intramuscularly, or intraocularly) or by intramuscular injection. Thus, for example, the compounds may be formulated with suitable polymeric or hydrophobic materials (for example, as an emulsion in an acceptable oil) or ion-exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt.
A pharmaceutical carrier for hydrophobic compounds is a cosolvent system comprising benzyl alcohol, a nonpolar surfactant, a water-miscible organic polymer, and an aqueous phase. The cosolvent system may be a VPD co-solvent system. VPD is a solution of 3% w/v benzyl alcohol, 8% w/v of the nonpolar surfactant polysorbate 80, and 65% w/v polyethylene glycol 300, made up to volume in absolute ethanol. The VPD co-solvent system (VPD:5W) cotains VPD diluted 1:1 with a 5% dextrose in water solution. This co-solvent system dissolves hydrophobic compounds well, and itself produces low toxicity upon systemic administration. Naturally, the proportions of a co-solvent system may be varied considerably without destroying its solubility and toxicity characteristics. Furthermore, the identity of the co-solvent components may be varied: for example, other low-toxicity nonpolar surfactants may be used instead of polysorbate 80; the fraction size of polyethylene glycol may be varied; other biocompatible polymers may replace polyethylene glycol, e.g. polyvinyl pyrrolidone; and other sugars or polysaccharides may be substituted for dextrose.
Alternatively, other delivery systems for hydrophobic pharmaceutical compounds may be employed. Liposomes and emulsions are known examples of delivery vehicles or carriers for hydrophobic drugs. Certain organic solvents such as dimethylsulfoxide also may be employed, although usually at the cost of greater toxicity. Additionally, the compounds may be delivered using a sustained-release system, such as semipermeable matrices of solid hydrophobic polymers containing the therapeutic agent. Various sustained-release materials have been established and are known by those skilled in the art. Sustained-release capsules may, depending on their chemical nature, release the compounds for a few weeks up to over 100 days. Depending on the chemical nature and the biological stability of the therapeutic reagent, additional strategies for protein stabilization may be employed.
The pharmaceutical compositions also may comprise suitable solid- or gel-phase carriers or excipients. Examples of such carriers or excipients include calcium carbonate, calcium phosphate, sugars, starches, cellulose derivatives, gelatin, and polymers such as polyethylene glycols.
Some of the compounds of the invention may be provided as salts with pharmaceutically compatible counter ions. Pharmaceutically compatible salts may be formed with many acids, including hydrochloric, sulfuric, acetic, lactic, tartaric, malic, succinic, etc. Salts tend to be more soluble in aqueous or other protonic solvents than are the corresponding free-base forms.
The preparation of preferred compounds of the present invention is described in detail in the following examples, but the artisan will recognize that the chemical reactions described may be readily adapted to prepare a number of other protein kinase inhibitors of the invention. For example, the synthesis of non-exemplified compounds according to the invention may be successfully performed by modifications apparent to those skilled in the art, e.g., by appropriately protecting interfering groups, by changing to other suitable reagents known in the art, or by making routine modifications of reaction conditions. Alternatively, other reactions disclosed herein or known in the art will be recognized as having applicability for preparing other compounds of the invention.